1
/* -*- coding: utf-8 -*- */
1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
3
* Passprompt - Read a password from the terminal and print it
5
* Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
3
* Password-prompt - Read a password from the terminal and print it
5
* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
7
8
* This program is free software: you can redistribute it and/or
8
9
* modify it under the terms of the GNU General Public License as
18
19
* along with this program. If not, see
19
20
* <http://www.gnu.org/licenses/>.
21
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
22
* <https://www.fukt.bsnet.se/~teddy/>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
25
25
#define _GNU_SOURCE /* getline() */
32
32
#include <signal.h> /* sig_atomic_t, raise(), struct
33
33
sigaction, sigemptyset(),
34
34
sigaction(), sigaddset(), SIGINT,
35
SIGQUIT, SIGHUP, SIGTERM */
35
SIGQUIT, SIGHUP, SIGTERM,
36
37
#include <stddef.h> /* NULL, size_t, ssize_t */
37
38
#include <sys/types.h> /* ssize_t */
38
39
#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE,
40
getopt_long, getenv() */
40
41
#include <stdio.h> /* fprintf(), stderr, getline(),
41
42
stdin, feof(), perror(), fputc(),
42
43
stdout, getopt_long */
50
51
ARGP_KEY_ARG, ARGP_KEY_END,
51
52
ARGP_ERR_UNKNOWN */
53
volatile bool quit_now = false;
54
volatile sig_atomic_t quit_now = 0;
54
56
bool debug = false;
55
const char *argp_program_version = "password-prompt 1.0";
57
const char *argp_program_version = "password-prompt " VERSION;
56
58
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
58
static void termination_handler(__attribute__((unused))int signum){
60
static void termination_handler(int signum){
65
signal_received = signum;
62
68
int main(int argc, char **argv){
73
79
struct argp_option options[] = {
74
80
{ .name = "prefix", .key = 'p',
75
81
.arg = "PREFIX", .flags = 0,
76
.doc = "Prefix used before the passprompt", .group = 2 },
82
.doc = "Prefix shown before the prompt", .group = 2 },
77
83
{ .name = "debug", .key = 128,
78
84
.doc = "Debug mode", .group = 3 },
82
error_t parse_opt (int key, char *arg, struct argp_state *state) {
83
/* Get the INPUT argument from `argp_parse', which we know is a
84
pointer to our plugin list pointer. */
88
error_t parse_opt (int key, char *arg, struct argp_state *state){
103
107
struct argp argp = { .options = options, .parser = parse_opt,
105
.doc = "Mandos Passprompt -- Provides a passprompt" };
106
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
107
if (ret == ARGP_ERR_UNKNOWN){
108
fprintf(stderr, "Unkown error while parsing arguments\n");
109
.doc = "Mandos password-prompt -- Read and"
110
" output a password" };
111
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
112
if(ret == ARGP_ERR_UNKNOWN){
113
fprintf(stderr, "Unknown error while parsing arguments\n");
109
114
return EXIT_FAILURE;
114
119
fprintf(stderr, "Starting %s\n", argv[0]);
117
122
fprintf(stderr, "Storing current terminal attributes\n");
120
if (tcgetattr(STDIN_FILENO, &t_old) != 0){
125
if(tcgetattr(STDIN_FILENO, &t_old) != 0){
121
127
return EXIT_FAILURE;
124
130
sigemptyset(&new_action.sa_mask);
125
sigaddset(&new_action.sa_mask, SIGINT);
126
sigaddset(&new_action.sa_mask, SIGHUP);
127
sigaddset(&new_action.sa_mask, SIGTERM);
131
ret = sigaddset(&new_action.sa_mask, SIGINT);
136
ret = sigaddset(&new_action.sa_mask, SIGHUP);
141
ret = sigaddset(&new_action.sa_mask, SIGTERM);
146
/* Need to check if the handler is SIG_IGN before handling:
147
| [[info:libc:Initial Signal Actions]] |
148
| [[info:libc:Basic Signal Handling]] |
128
150
ret = sigaction(SIGINT, NULL, &old_action);
130
152
perror("sigaction");
131
153
return EXIT_FAILURE;
133
if (old_action.sa_handler != SIG_IGN){
155
if(old_action.sa_handler != SIG_IGN){
134
156
ret = sigaction(SIGINT, &new_action, NULL);
136
158
perror("sigaction");
167
189
fprintf(stderr, "Removing echo flag from terminal attributes\n");
171
193
t_new.c_lflag &= ~ECHO;
172
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
194
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
173
195
perror("tcsetattr-echo");
174
196
return EXIT_FAILURE;
178
200
fprintf(stderr, "Waiting for input from stdin \n");
205
fprintf(stderr, "Interrupted by signal, exiting.\n");
182
207
status = EXIT_FAILURE;
187
fprintf(stderr, "%s Password: ", prefix);
189
fprintf(stderr, "Password: ");
212
fprintf(stderr, "%s ", prefix);
215
const char *cryptsource = getenv("cryptsource");
216
const char *crypttarget = getenv("crypttarget");
217
const char *const prompt
218
= "Enter passphrase to unlock the disk";
219
if(cryptsource == NULL){
220
if(crypttarget == NULL){
221
fprintf(stderr, "%s: ", prompt);
223
fprintf(stderr, "%s (%s): ", prompt, crypttarget);
226
if(crypttarget == NULL){
227
fprintf(stderr, "%s %s: ", prompt, cryptsource);
229
fprintf(stderr, "%s %s (%s): ", prompt, cryptsource,
191
234
ret = getline(&buffer, &n, stdin);
193
fprintf(stdout, "%s", buffer);
194
236
status = EXIT_SUCCESS;
237
/* Make n = data size instead of allocated buffer size */
239
/* Strip final newline */
240
if(n>0 and buffer[n-1] == '\n'){
241
buffer[n-1] = '\0'; /* not strictly necessary */
246
ret = write(STDOUT_FILENO, buffer + written, n - written);
249
status = EXIT_FAILURE;
252
written += (size_t)ret;
198
if (errno != EINTR and not feof(stdin)){
257
if(errno != EINTR and not feof(stdin)){
199
258
perror("getline");
200
259
status = EXIT_FAILURE;
204
263
/* if(ret == 0), then the only sensible thing to do is to retry to
205
264
read from stdin */
206
265
fputc('\n', stderr);
266
if(debug and not quit_now){
267
/* If quit_now is nonzero, we were interrupted by a signal, and
268
will print that later, so no need to show this too. */
269
fprintf(stderr, "getline() returned 0, retrying.\n");
210
276
fprintf(stderr, "Restoring terminal attributes\n");
212
if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
278
if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &t_old) != 0){
213
279
perror("tcsetattr+echo");
217
fprintf(stderr, "%s is exiting\n", argv[0]);
283
sigemptyset(&old_action.sa_mask);
284
old_action.sa_handler = SIG_DFL;
285
ret = sigaction(signal_received, &old_action, NULL);
289
raise(signal_received);
293
fprintf(stderr, "%s is exiting with status %d\n", argv[0],
296
if(status == EXIT_SUCCESS){